Prodigious amounts of energy are used to power automobiles, heat homes, manufacture products, generate electricity, and perform various other tasks. In order for our society to function in its present patterns, vast amounts of coal, natural gas, and oil are extracted from the Earth and burned to provide this energy. We also derive energy from hydroelectric plants, nuclear reactors, electric wind generators, and geothermal plants, and of course, we all benefit enormously from the energy obtained directly from the sun.

Since the beginning of the machine age, industrial societies have become increasingly dependant on fossil fuels. Now less than one percent of our energy comes from firewood and we rely on the physical effort of people and animals.

Should we be concerned that so much of our energy is now coming from fossil fuels? Here are two of many factors that should cause concern.

First, the fossil fuel resource is limited in amount. The fossil fuels were produced by solar energy hundreds of millions of years ago, and when they are gone, there will be no more. How long will they last? On a global scale we will still have some coal for a few centuries, but natural gas and oil will be in short supply in only a few decades. The entire stock of fossil fuels available for our use has been held in storage under the Earth’s surface for more than a hundred million years, and now is being completely exploited in only a few centuries.

Second, unintended environmental consequences result from the extensive scale of our use of the fossil fuels for everything from heating our homes to powering our automobiles.

This is causing problems we are just beginning to face. The atmospheric pollution is producing health problems and even death, and it is now becoming recognized that carbon dioxide emissions are threatening to produce climate changes over the entire globe.

Can we find solutions to these problems of resource depletion and environmental pollution? The subject is complex and first of all, we, people, need a rational decision-making process.

Energy consumption can be related to the general well-being of a populace. The advantages of convenient transportation, abundant food and water, comfortably heated and cooled residences and places of work, ample production of goods, and many aspects of the good life involve the consumption of energy. The problem of high level of energy consumption arises in two areas. The first has to do with resource depletion. The majority of our energy supply is derived from fossil fuels. The resources of coal, petroleum, and natural gas are being depleted in the world at alarming rates. We have consumed more natural gas than we have discovered nearly every year for the past twenty years, and we will probably see shortages within a decade or two. Production of petroleum from domestic sources has gone down rather steadily. We now import more than half of the petroleum that we use. The balance-of-trade deficit is seriously affected by purchases, which are likely to increase with time.

The second aspect of the problem relates to the emission into the atmosphere of the byproducts of burning any fossil fuel. The rate at which we are burning fossil fuels worldwide has reached a point where restraint must be considered.

Energy Conservation

According to a well-established law of physics the total energy in an isolated region can neither enter nor escape that region, that is, it is conserved, even though it may be transformed from one form of energy to another ( i.e. kinetic energy can become thermal energy, or, as to A. Einstein’s theory, energy can be converted to mass (rest mass) and mass converted to energy). Energy cannot be created or destroyed. This is the principle of Energy Conservation, according to which, the total energy remains the same, its usefulness for performing tasks has certainly been diminished.

energy conservation is distinct from the Principle of Energy Conservation and applies to the idea of using less energy to perform a given task. An example of energy conservation would be the installing of better insulation in the walls of a house in order to allow one to maintain the interior at a comfortable level on a cold winter day with the use of less fuel in the furnace.